排序方式: 共有46条查询结果,搜索用时 187 毫秒
41.
根据在相同的环境温度下和不同环境温度下对船体轴系部位同一材料、相同结构的多个目标点进行反复测量,观察全站仪测量数据的变化,分析环境温度变化引起的误差情况,为船舶精度建造工艺研究提供可靠的数据支撑。 相似文献
42.
43.
44.
45.
《中国航空学报》2022,35(8):143-157
The damage effect assessment of anti-ship missiles combines system science and weapon science, which can provide reference for the assessment of battlefield damage situation. In order to solve the difficulty of heterogeneous data aggregation and the difficulty in constructing the mapping between factors and damage effect, this paper analyzes the specific damage process of the anti-ship missile to the ship, and proposes a synthetic Evidential Reasoning (ER) – Adaptive Neural Fuzzy Inference System (ANFIS) to assess the damage effect. To solve the problem of fuzziness and uncertainty of criteria in the assessment process, the belief structure model is used to transform qualitative and quantitative information into a unified mathematical structure, and ER algorithm is used to fuse the information of lower-level criteria. In order to solve the problem of fuzziness and uncertainty of the information contained in the first-level variables, and the strong non-linear characteristics of the mapping between first-level variables and damage effect, the ANFIS with self-adaptation and self-learning is constructed. The map between the three first-level variables and damage effect is established, and the interaction process of the various factors in the damage effect assessment are clear. Sensitivity analysis shows that assessment model has good stability. The result analysis and comparative analysis show that the process proposed in this paper can effectively assess the damage effect of anti-ship missiles, and all criteria data are objective and comparable. 相似文献
46.
在分析船只三维转动(横滚、俯仰、偏航)对合成孔径雷达(Synthetic Aperture Radar,SAR)成像质量的影响方面,现有文献只考虑了仅存在一维转动时的影响,未考虑三维转动同时存在时对SAR成像质量的影响。另外,现有文献主要基于船只转动对船只散射点瞬时多普勒频率的影响进行分析,并未真正与对SAR图像质量的影响关联起来。本文推导了适用于船只存在三种一维转动、同时存在三维转动时的SAR图像二维时域表达式,以及散射点方位向坐标的表达式。在上述表达式的基础上,通过分析船只上的散射点在SAR图像中的偏移情况,扩展到分析船只整体在SAR图像中的形变情况;通过分析一维转动对SAR成像的影响,扩展到分析三维转动同时存在时对SAR成像的影响。研究表明:船只三维转动引入了包络误差和相位误差,导致SAR图像中散射点模糊并在方位向偏移,且不同散射点的偏移量不同,从而使船只形状发生畸变。仿真结果验证了所推导表达式的准确性及理论分析的正确性。 相似文献